Carburetor



C. E. DE FORREST. CARBURETOR.

APPLICATION min www. 1919.

1,403,848. Patented Jan. 17, 1922.

In yew 17011* '.e/Ffofrecf resin, a citizen of the i UNITED STATES PATENT GFFICE.,

CARBURETOR.

Application led .Tuly 31,

To aZZ whom t may concern.'

Be it known that I, CHARLES E. DE FoR- United States, residing at Chester, in the county of Delaware and State of Pennsylvania, have invented certain new and useful Improvements in Carburetors, of which the following is a specifcation.

The purpose of this invention is to produce a carburetor for use in connection with internal combustion engines orwith heating and lighting apparatus.

A feature of the invention is the omission of all movable-parts within the tank,`and thereby are eliminated the matters of adjustment in the sizes of openings such as valves or in the setting of parts, and the sticking of parts or their clogging by the presence of particles of extraneous matter is avoided, The elements of this device having 5onge been chosen of proper size and properly connected, the action is entirely automatic, whether the product is exhausted from the tank by suction or the air is forced into the tank by pressure, or in some cases, possibly both. I prefer to employ suction when the fuel is used for a motor, and I prefer to pump in the. air when the fuel is to be used for lighting or heating.

Another feature of this invention is the provision of means whereby the last particle of gasoline within the tank will be consumed, and the apparatus will function successfully to the last moment. l Details of my preferred construction are described below and shown in the drawings wherein- Figure 1 is a vertical section through the carbureter complete.

Figure 2 is a horizontal section line 2-2 of Figure 1;

Figure 3 is a detail sectional view illustrating an embodiment of the invention;

igure 4 is adetail section on the line 4 4 of Fig. 3.

The numeral 1 designates a tank entirely closed excepting as described below, and 2 1s a nipple around its filling opening, which nipple will be ordinarily closed by a cap 3. Air is -admitted through a strainer 4 and check valve 5, and thence through a pipe 6 through the top 0f the tank. The fuel is exhausted through a pipe 7 and check valve 8, beyond which t-he'pipe 9 leads to a motor or possibly to a tank to be stored until otherwise used; The vcheck valve 5 yprevents the escape of any products except through the on the Specification of Letters Patent.

y strainer 15 standing 1919. Serial No. 314,408.

pipe 7 and the check valve 8 prevents ignition within the tank resulting from possible backfire from an engine.

As shown herein, the tank is by preference rectangular, and is provided in its bottom 10 with a large opening 11 beneath which is a pan 12 constituting a sump or well whose bottom is therefore below the lowest level of the gasoline within the tank. Within this sump I locate a coil 13 whose inner or outlet end 14 preferably carries a level with the bottom 10 of the tank. Connected with or formed as a continuation of the inlet end of this coil is an upstanding tubular column 16 rising through the gasoline in the tank and closed at its upper end at 17, and the air inlet pipe 6 leads through suitable connections 18 and 19 into theside of this column near its closed upper end.

The numeral 20 designates a siphon in the shape of a fine pipe, possibly of copper tubing, clipped 21, alongside and upon the exterior of the column 16, its lower end 22 extending down past the top of the coil, whereas its upper end is vdeflected as at 23 bent over the top as at 24, carried down through the. upper 4end 17 on the column,'and directed downward, as at 25, along the axisof the column and across the inner end of the air inlet pipe 19 to terminate belowfsaid pipe.

While the mechanical Ydetails are not important, provision should be made for connecting the parts in such manner that they are removable and-acce`ssible so far as possible, and for this purpose it may be well to have the nipple 2 of such size that the hand may be extended through it. The inlet end of the coil carries an upstanding nipple 30 flanged at its upper end, as at 31, and the lower end of the column may have an outstanding ange 32 overlying the flan'e 31 and detachably connected thereto by bo ts 33. A sheet of foraminous material or other form of strainer 34 may be inserted between the flanges 31 and 32 to "divide and agitate the inflowing air, being held removably betweenl the flanges when the nuts on the bolts are turned home. The'connection between theair inlet pipe and the upper portion of the column may be adetachable one at any one of several points, as, for instance, where the short pipe or nipple 19 is screwed to the column. Both the I let pipe 7 may pass through holes in the Patented Jan. 17, 1922.

or otherwise secured, as at l'oc inlet pipe 6 and the out-fA -either or boththese strainers may be employed. The primary strainer 4 is shown as carried by the upperl end of a bell 42 whose stem is mounted in the casing of the check valve 5. The strainers herein referred to may be foraminous metal, fabric, or other material, as desired. A suitable drain valve 43 is preferably threaded in the bottom of the pan 12 to permit drainage of said pan when necessary.

In Fig. 1, the end of the coil is shownI as bent upwardly, but in Figs.v 3 and 4 it is threaded in a coupling 44, the latter being spaced inwardly from the edge of the pan. A short tube"or pipe section 45 is disposed horizontally in'A the coupling 44 or the upbent end of the coil with one end thereof communicating with the interior of the coil and its other end opening into the pan 12 through the side of the coupling 44 or the upturned end of the coil as the case may be, so that as fuel is sucked through the strainer' 15 a portion of the gasoline in the pan will enter the coil through the pipe 45 and thus increase the circulation of the fuel through said coil. I will thus effect a very thorough commingling of the air and gasoline and a more complete atomizing of the gasoline as well 'as causing practically every drop of the gasoline to be used. It will b" understood that the employment of the tube 45 is optional. employed in connection with the Siphon Atube 20 in whichl event it will Abe arranged within the bend which connects the coil 13 with the lower end of the pipe 16. f

Assuming that`the tank is filled with gasoline about to the level shown in Figure 1 and suction applied to the pipe 9, the action will be as follows: Air enters through the strainer 4 and check valve 5, flows along the pipe 19 and into the upper end of the column 16 and upon the gasoline within ythe column which, of course, 'stands at the same level as that outside the column. Suction causes thisy air to pass downward into the coil 13, throughout the length of the coil which is filled with asoline, upward throughv its outlet 14 an the strainer 15, and thence upward in the form of bubbles or lobules through the volume of gasoline wit in the tank,v out the outlet 7 and past the checky valve 8, to the engine vor other point desired. During this course the air becomes thoroughly mixed with gasoline, and the' product passing through the outlet 7 is thereforey carbureted air rather than atomized gasoline. The 'circulation'initially That is to say it 'may be set up may exhaust the fuel from the column 16 but the inflowing air will thoroughly` commingle with the gasoline as the latter recedes from the column. The extremity 25 of the siphon tube 20 being below the pipe 19, the air will iow past but not across said extremity and exert a suction thereon, with the result that a small amount of gasoline is drawn upward through the Siphon and delivered into the inflowing .air which is thus, to an extent, charged with gasoline even before it'starts on its course through the vcolumn and coil. The degree to which this jet of gasoline may be atomized will depend on the shape imparted to the extremity 25 and will to a large extent depend on the grade of the gasoline employed. I might even say that while I have spoken of gasoline throughout this specification, it is obvious that other volatile liquid fuels or agents might be used instead, and while I have spoken of air, inferring that it would be atmospheric air admitted, it is quite possible to mix the air with other substances which combine most effectively with the liquid fuel used, to producei an' eicient product for the purpose des1re The siphon pipe utilizes the suction produced by the draft of air to raise a small quantity of gasoline and constantly jet itdownward into the incoming air, and thus the air is to an extent chargedy even before it begins its passage through the column. Also the siphon action of the fine pipe makes it possible to consume every particle of gasoline within thetank and practically all that in the sump.

I lconsider the coil also an important feature of the structure, it's chief function being to retard the carbureted air and prolong its time of assage between the column and the point w ere it rises through the gasoline in the tank. i In other words,.it presents a tortuous course through which the already charged air must flow, wholly submerged, so that it becomes yet furthercharged before it is permitted to rise vthrough the free gasoline and pass off.

In closing, I call attention to the factthat, excepting for the two check valves fully outside the tank, the structure has no valve whatever and no movable part. No adjustment is necessary, all parts having once been properly l selected and assembled. The

.action is entirely automatic from start to finish, and atomized fuel is delivered just as well with a tank nearly full as with a tank nearly empty. Even when the level of the gasoline falls to a point below the i line of the bottom 10, atomization will still be effected from the gasoline remaining within the coil,l and the same strength of gaseous fuel will be produced so long `as' the Siphon pipe functions as described.-

Having thus described the invention, what is claimed as new is: l

l. A carburetor comprising a reservoir for the carbureting fluid, an air intake conduit having one end opening exteriorly of the reservoir and its other end opening into the reservoir, an outlet conduit for the mixture leading from the reservoir above the fluid level therein, and a Siphon tube having an intake endopening into the reservoir below the fluid level and a dischargev end opening into the said air intake conduit.

2., A carburetor comprising a reservoir for the carbureting fluid, an air intake conduit having one end,v opening exteriorly of the reservoir and having its lower end provided, within the reservoir, with a coil and with a branch leading from the coiland opening into the reservoir, an outlet conduit for the mixture leading from the reservoir above the Huid level therein, and a Siphon tube having an intake end opening into the reservoir below the fluid lev`el and a discharge end opening into the said air intake conduit above the fluid level.

3. A carburetor comprising a reservoir for the carbureting fluid, an air intake conduit having one end opening exteriorly of the reservoir and its other end opening into the reservoir, an outlet conduit for the mixture leading from the reservoir above the fluid level therein, a Siphon tube having anintake end opening into the reservoir below the fluid level-and a discharge end opening into the said air intake conduit, and a Huid inlet i e establishinv a communication between air intake conduit at a discharge end of the the reservoir and the point adjacent thelatter.

In testimony whereof I afilix my signature.

CHARLES E. DE FORREST. [L s.] 

